Process for the dyeing of modified polyester fibers with basic dyes in the presence of aromatic carboxylic acids

ABSTRACT

This invention provides a novel process for the dyeing of fibrous materials such as yarn, filaments and textile fabrics made of modified synthetic polyesters which contain a sulfonate radical, or blended yarn fabrics or union cloths containing said fibrous materials of modified polyester with basic dyestuffs in a dye bath containing at least one of the aromatic carboxylic acids represented by the general formula WHEREIN R denotes a hydrogen atom or radical selected from the group consisting of hydroxyl and carboxyl groups serving as dyeing accelerator. The dyeing process according to the present invention is advantageously carried out with a rapid adsorption of the dyestuff from dye bath resulting in a deep shade of coloration on the materials having an outstanding fastness properties especially light-fastness.

United States Patent Ozutsumi et a1.

May 2, 1972 [54] PROCESS FOR THE DYEING OF MODIFIED POLYESTER FIBERS WITH BASIC DYES IN THE PRESENCE OF AROMATIC CARBOXYLIC ACIDS [72] Inventors: Minoru Ozutsumi; Kazuo Kawakami;

Sumio lshizaki, all of Tokyo, Japan [73] Assignee: Hodogaya Kagaku Kogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Jan. 24, 1969 [21] AppLNo: 793,755

[56] References Cited UNITED STATES PATENTS 3,132,132 5/1964 Suzuki etal. ..260/158 3,136,751 6/1964 Dizukaetal ....260/l58 3,097,047 7/1963 Weinstein etal. ..8/166 FOREIGN PATENTS OR APPLICATIONS 1,096,943 12/1967 Great Britain .-...8/93

OTHER PUBLICATIONS D. P. l-lallada et al., Amer. Dyestuff Reporter, June 12, 1961, pp. p445- p450 Exparte Schoeneberg et al., Decision of the Board of Appeals, Patent No. 3,190,718, paper No. 27, 4 pages.

DYE-EXHAUSTION FROM DYE-BATH /0) TIME FOR DYEING (MINUTES) Exparte Schoonover et al., Decision of the Board of Appeals, Patent No. 2,743,991, paper No. 23, 6 pages.

Primary Examiner-George F. Lesmes Assistant Examiner-T. J. Herbert, Jr. An0rneyWenderoth, Lind & Ponack [5 7] ABSTRACT This invention provides a novel process for the dyeing of fibrous materials such as yarn, filaments and textile fabrics made of modified synthetic polyesters which contain a sulfonate radical, or blended yarn fabrics or union cloths containing said fibrous materials of modified polyester with basic dyestuffs in a dye bath containing at least one of the aromatic carboxylic acids represented by the general formula CIOOH wherein R denotes a hydrogen atom or radical selected from the group consisting of hydroxyl and carboxyl groups serving as dyeing accelerator.

The dyeing process according tare present invention is advantageously carried out with a rapid adsorption of the dyestuff from dye bath resulting in a deep shade of coloration on the materials having an outstanding fastness properties especially light-fastness.

4 Claims, 1 Drawing Figure PATENTEnMm I972 3660,01 5

DYE-EXHAUSTION FROM DYE-BATH U1 o 5 IO "I5 3o 60 TIME FOR DYEING (MINUTES) INVENTORS MINORU OZUTSUM] KAZUO KAWAKAMI SUMIO ISHIZAKI ATTORNEYS This invention relates to a process for the dyeing of fibrous materials such as yarns, filaments and textile fabrics made of sulfonate radical-containing modified synthetic polyesters or blended yarn fibrics as well as union cloths containing such sulfonate radical-containing polyester fibers, with basic-type dyestuffs.

By the expression sulfonate radical-containing modified synthetic polyesters throughout the specification and the appending claims is meant the synthetic polyesters modified by introducing a sulfonate radical into the polyester molecule such as those mentioned in the specifications of British Pat. No. 868,497 and U.S. Pat. No. 3,018,272, for example. Likewise by the expression basic-type dyestuffs" is meant the cationic dyestuffs which have recently been developed to be particularly adapted for dyeing of acrylic fibers, in addition to the conventional basic dyestuffs hitherto known.

The primary object of the present invention is thus to provide a novel process for the dyeing of the fibrous materials made of modified synthetic polyesters containing a sulfonate radical with the aforementioned basic-type dyestuffs to produce thereon dyeings having the excellent fastness properties especially light-fastness.

Polyethylene terephthalate fibers which are also known as polyester fibers, owing to the fact that they possess a definite and regular structural configuration of the molecule and high crystallinity, fail to absorb dyestuff molecules from dye bath. They therefore are considered as materials difficult to be dyed.

As the result of many efforts that have been directed to this field to overcome the aforementioned difficulty, certain modified polyester fibers having an improved dye-acceptability are at present available on the market. The improvement in dyeability of such fibrous materials of the polyester has been established either by introducing a radical having an affinity toward dyestuff molecule into the polyester molecule, or by relaxing or loosening the crystalline structure of the fibrous material to allow penetration of the dyestuff molecules thereinto. For instance, filament yarns of Dacron 62 and staple yarns of Dacron 64, both being the products of E. l. du Pont, are the anionic modified polyester fibers readily dyeable with cationic as well as disperse dyestuffs. These polyester fibers are prepared by introducing a sulfonate radical having a strong polarity into the molecule of said polyester or by partially converting its terephthalate moiety into isophthalate moiety to bring about an irregularity of its crystalline structure.

Even though the dyeability of such fibrous materials of polyester thus obtained are apparently improved, there remains a difficulty in that deep shade of coloration cannot be obtained when the materials are dyed in accordance with a standard dyeing procedure such as that employed for other known hydrophobic synthetic fibers. With hydrophobic dyestuffs such as disperse dyestuffs, dyeing of the above-mentioned modified polyester fibers is thus usually conducted either at a temperature above 100 C. under pressure or at atmospheric pressure by the aid of a carrier. As is well known, dyeing of such fibers is conducted in analoguous manner with a known basic dyestufi by the aid of a carrier such as Latyl Carrier A, a product of E. I. du Font, and o-phenylphenol. (See D. P. Hallada et al., American Dyestuff Reporter, 50, 448, (1961).) Unfortunately, with such dyeing procedure using Latyl Carrier A or o-phenylphenol, there can hardly be obtained a dyeing having a good light-fastncss. The dyed product is therefore known as a little worth from commercial viewpoint. In spite of that, since basic dyestuffs generally produce dyeings possessing excellent fastness properties to sublimation, hot water and various organic solvents, they nevertheless, are widely employed, even though not satisfactorily, in dyeing of the fabrics such as those for women's garments which require colorful, attractive shades.

Now, as the result of extensive investigations, we have established a novel process for dyeing of the aforementioned fibrous materials made of modified polyester with basic-type dyestuffs. Attractive dyeings of deep shades having excellent fastness properties are thus obtained by carrying out the dyeing process of the present invention at a temperature of about C. to C. and in the presence of at least one of the aromatic carboxylic acids represented by the general formula (IJOOH wherein R designates hydrogen atom or substituent selected from the group consisting of hydroxyl and carboxyl radicals.

Accompanying drawing (FIG. 1) shows dyeing characteristic with regard to the rate of dye-absorption on Dacron 62 at a constant temperature. The dyeing was carried out in the dye baths containing (C. I. Basic Yellow 11 (Cl. No. 48055) and benzoic or salicylic acids at temperature of 95 C. A control dyeing was also carried out in a similar manner without using any organic carboxylic acid.

As for the preferred aromatic carboxylic acids having aforementioned general formula, there may be mentioned benzoic, phthalic, salicylic acids and so on. In carrying out the dyeing, at least one of these aromatic acids is used by dissolving it in the dyestufl" solution to'be employed. The amount of the acid or acids to be used may vary within a wide range depending upon the desired depth of shade. And, in practice, 0.1-15 grams and preferably 0.5-7 grams of the acid or acids per liter of the dye liquor it found recommendable. These aromatic acids, if desired, may also be added to the dye liquor as a solution dissolved in a lower fatty acid such as formic and acetic acids, an alcohol such as methyl and isopropyl alcohols. Alternatively, the aromatic acids may be added to dye bath in a form of an aqueous dispersion prepared by the aid of a nonionic surfactant such as polyethylene glycol lauryl ether, polyethylene glycol nonylphenol ether and the like. The dyeing may be conducted with a basic-type dyestuffs such as those hitherto known conventional basic dyestuffs as well as the recently developed cationic dyestuffs in accordance with the conventional dipping, padding and printing procedures.

A certain aromatic carboxylic acid had been used as an effective dye carrier for non-modified polyester fibers with a disperse dyestuff. However, in order to obtain a satisfactory effect on the dyeing, it was found that use of a considerable amount such as more than 20 grams of the acids per liter of the dye liquor is needed. Consequently, the use of aromatic carboxylic acid as a dyeing carrier became uninteresting in economical viewpoint, and nowadays the method is almost disregarded. (Comp. D. P. Hallada et al., American Dyestuff Reporter, 50, 445 (1961).)

It was therefore not known and is surprising that the specified aromatic carboxylic acid acts an extraordinary dyeing carrier for dyeing of the sulfonate radical-containing modified polyester fibers with the basic-type dyestuffs according to the process of the present invention.

Most of the conventional dyeing carriers hitherto employed, as is known, are not only toxic to human body and possess an unpleasant odor, but also show a bad effect on light-fastness of the resultant dyeings. In order to avoid such bad effect, it is therefore necessary to completely remove any remaining dyeing carrier from the dyed material after the dyeing was finished, the step of such complete removal of the acid being found considerably troublesome.

In contrast to the above, the process of the dyeing according to the present invention has an advantage that there is no need of such troublesome step for removing the remaining aromatic acid because the same is non-toxic, and odorless and has no harmful effect on the resultant dyeings.

The process of the present invention is illustrated more concretely by the following examples, per cent specified in these examples being based on the weight of the fibrous material to be dyed.

EXAMPLE 1 2 grams of scoured dry Dacron 62 were dyed at liquor ratio of 50:1 under hereafter-mentioned dyeing conditions with 1.5 percent of (C1. Basic Yellow 11 (Cl. No. 48055) the maximum absorption wave length of 410 my), and inspected the effects of the dyeing carrier, i.e., benzoic and salicylic acids, on the rate of adsorption of the dye from the dye bath at the constant temperature of 95 C. The exhaustion of the dyestufi was determined periodically by photometric measurement of the remaining dye in the bath during a definite dyeing time.

The results obtained are shown in the accompanying drawing (FIG. 1).

In FIG. 1, the curve A shows the result of the dyeing as control which was carried out with the dye liquor in the presence of 0.5 percent of sodium acetate and adjusted the pH value to 4 by means of acetic acid, and without employing aromatic carboxylic acid (the dyeing method is hereafter called as Example 1-A control dyeing method).

The curve B is the result of dyeing with the dye bath containing 5 grams of salicylic acid as a dyeing carrier per liter of the dye liquor, and the curve C is the result of dyeing with the dye bath containing 5 grams of benzoic acid as a dyeing carrier per liter of the dye liquor, the both being in accordance with the process of the present invention.

As will be seen from the Figures, the curve A exhibits 87 percent exhaustion of the dyestuff from the dye liquor after 60 minutes of the dyeing at constant temperature of 95 C., while the curvges B and C exhibit equally almost 100 percent exhaustiori of the dyestuff at constant temperature of 95 C. only after minutes of the dyeings.

As is evident from the above, the rate of adsorption of the dyestuff from the bath caused by the specified dyeing material according to the process of the present invention is remarkably advanced, and so, it is possible to save considerably the time required for dyeing.

EXAMPLE 2 A dye bath was prepared containing 1.5 percent of Cl. Basic Red 39, the maximum absorption at the wave length of 520 mp, which is represented by the formula (-11 0 IIgCONllg and 5 grams of benzoic acid per liter of the dye liquor, the benzoic acid having been added as a solution in a small quantity of methanol.

The bath was warmed to 50 C. and 2 grams of scoured Dacron 62 were entered into the bath at the liquor ratio of 40:1. After 30 minutes, the temperature of the bath was raised to 100 C., and at this temperature the dyeing was continued for 60 minutes. During that time, the period of the time required for the complete exhaustion of the dyestuff from the bath was inspected and was found it took place enough just before the boiling of bath commenced.

In a similar manner, a dyeing of Dacron 62 was carried out with exception that the dye bath throughout the dyeing was kept at 100 C., in accordance with the procedure of Example 1-A control dyeing method. The dyestuffs was completely taken out by the fibrous material from the dye bath barely after minutes after the temperature of the bath was elevated to 100 C.

Although the level and deep dyeings were equally obtained in the aforementioned two cases, the dyeings were differentiated from each other with respect to light-fastness measured in accordance with the method disclosed in 180 R 105/ 1, Part 11. The dyeing obtained by the control dyeing method presented the light-fastness of Grade 4, while the dyeing obtained by the procedure which was conducted by the aid of benzoic acid as a dyeing carrier in accordance with the process of the present invention presented the light-fastness of Grade 5.

Another comparison test of dyeing was carried out in accordance with the Example l-A control dyeing method, at temperature of C. for 60 minutes in a high pressure, high temperature dyeing machine. A dyeing was thus obtained which possessed a good light-fastness comparable to that obtained by the dyeing procedure at temperature of 100 C. for 60 minutes in the presence of benzoic acid in accordance with the aforementioned example.

EXAMPLE 3 2 grams of scoured dry Dacron 64 were dyed with a dye bath of the liquor ratio of 40:1 and at temperature of 100 C. for 60 minutes. The dye bath contained 1.5 percent of CI. Basic Blue 66, the maximum absorption wave length of 615 mp, which is represented by the formula g1 C 11 1i 2116i:

and 3 grams of o-phthalic acid per liter of the dye liquor. The o-phthalic acid was added as an aqueous solution prepared by dissolving the same in a small quantity of hot water. The lightfastness of the dyed material was measured as Grade 5-6, which was almost equal to that obtained by the dyeing that effected at C. for 60 minutes with the corresponding dye bath containing no o-phthalic acid in accordance with the high temperature dyeing method.

Another dyed material obtained by the dyeing procedure as shown in Example l-A control dyeing method with exception that the dyeing was conducted at temperature raised to 100 C., exhibited the light-fastness of Grade 3-4.

EXAMPLE 4 2 grams of scoured dry Dacron 64 were dyed in the manner similar to that of the preceding Example with a dye bath containing 6 grams of salicylic acid and 1.5 percent of Cl. Basic Yellow 11 (CI. No. 48055) the maximum absorption wave length of410 my.

A control dyeing was separately carried out at elevated temperature of 105 C. for 60 minutes by using the same dye bath same as that employed in the above Example without the addition of salicylic acid.

The two dyed materials thus obtained had almost the same depth of shade. The light-fastness of the control was measured as Grade 4-5, while the dyed material obtained from the aforementioned dye bath containing salicylic acid possessed the light-fastness of Grade 6.

EXAMPLE 5 The dyeings of each 2 grams of scoured dry Dacron 62 were carried out at temperature of 100 C. for 60 minutes at the liquor ratio of 40:1. The dye baths contained respectively 5 grams of the mixed black dyestuffs composed of the dyestuffs listed below with or without 5 grams of benzoic acid per liter of the dye bath.

a. C1. Basic Orange 21 (C.l. No. 48035) b. C.l. Basic Yellow 11 (Cl. No. 48055) c. C.I. Basic Blue 65 represented by the formula 4312012120 ONHZ d. C]. Basic Violet l (C.I. No. 42535)) e. (C.I. Violet l4 (C.I. No. 42510) f. (C. I. Basic Green 4 (C.I. No. 42000) g. C.I. Basic Blue 3 (C.I. No. 51005) h. C.I. Basic Brown 1 (C.I. No. 21000) The benzoic acid was added in a form of aqueous solution prepared with a small quantity of hot water.

A dyeing of deep black shade having light-fastness of Grade 4 was thus obtained.

A control dyeing was separately carried out under the conditions same as those above-mentioned with exception that a dye bath was used which contained no benzoic acid.

A dyeing of pale gray in shade was thus obtained having a light-fastness of Grade 1.

EXAMPLE 6 A union cloth of Dacron 64 as warp and wool as woof was first dyed at liquor ratio of 40:1 of a dye bath containing 1.0 percent CI. Basic Blue 66 used in Example 3 and 5 grams of benzoic acid per liter of the liquor. The benzoic acid was added as an aqueous solution in a small quantity of hot water. The dyeing was carried out by entering the fabric into the dye bath kept at 50 C., and in the course of 30 minutes the temperature of the bath was raised to 100 C. At this temperature, the dyeing was continued for 60 minutes to subject a selective dyeing of the warp fibers of Dacron in the union cloth. The dyed material was then rinsed well with water.

The fabric was then treated with a reduction cleaning bath at the liquor ratio of 30:1 and at temperature of 70 C. for about 10 minutes. The reduction cleaning bath contained 2 grams of sodium hydrosulfite per liter of the liquor and 4 percent of a 30 percent acetic acid. The treated fabric was rinsed with water and entered into another dye bath at 50 C. which contained 1.5 percent of C1. Acid Blue 59 (C.I. No. 50315) 10 percent of anhydrous Blauber's salt and 2 percent of glacial acetic acid. The whole was gradually heated to boil and the dyeing was continued for 60 minutes at the boiling temperature in order to secure the performance of dyeing of the woof fibers in the union cloth. There was thus obtained a satisfactorily dyed union cloth.

Another dyeing was carried out on the same union cloth as that of the preceding paragraphs. The first step dyeing of Dacron fibers on the fabric was effected at temperature of 105 C. for 60 minutes by using a dye bath containing Aizen Cathilon Blue NBLH as aforementioned but without benzoic acid, in a high pressure-high temperature dyeing machine in accordance with Example l-A control dyeing method. The dyed fabric was further worked with a second dye bath similar to that employed in the preceding paragraph to cause dyeing of the wool fibers in the union cloth. There was obtained a dyed material having almost the same property as that obtained in the steps given the preceding paragraphs.

EXAMPLE 7 A dye bath of a liquor ratio of 40:1 was prepared which contained 1.5 percent of Cl. Basic Blue 67, a maximum absorption wave length of 590 my. which is represented by the formula 3 grams of benzoic acid and 2 grams of salicylic acid per liter of the dye bath. The benzoic acid and salicylic acid were added in a form of an alcoholic solution prepared by dissolving them in a small quantity of methanol;

To the bath at 50 C. were entered 2 grams of scoured Dacron 62. In the course of 30 minutes, the temperature of the bath was raised to C. At this temperature, the dyeing was continued for 60 minutes.

For the sake of comparison, other two dyed materials were prepared with a dye liquor similar to that used in the preceding paragraphs but containing no benzoic and salicylic acids as dyeing carrier. The dyeings were carried out in accordance with the teachings of Example l-A control dyeing methods; the one of the dyeings was effected at temperature of 100 C. and at atmospheric pressure and the other at temperature of C. in a pressure dyeing machine, both for 60 minutes.

Light-fastness of these dyed pieces were measured, and the results observed are as follows:

What is claimed is:

1. A process for dyeing fibrous materials of modified synthetic polyesters containing a sulfonate radical, textile fabrics, blended yarn fabrics or union cloths containing said polyester fibers wherein the dyeing is carried out at a temperature of 95-100 C. with a dye bath containing a basic dyestuff and at least one aromatic carboxylic acid of the formula (IZOOH wherein R represents hydrogen, hydroxyl or carboxyl as carrier at a concentration of 0. l-l 5 grams per liter.

2. A process according to claim 1 wherein the aromatic carboxylic acid is benzoic acid.

3. A process according to claim 1 wherein the aromatic carboxylic acid is salicylic acid.

4. A process according to claim 1 wherein the aromatic carboxylic acid is o-phthalic acid. 

2. A process according to claim 1 wherein the aromatic carboxylic acid is benzoic acid.
 3. A process according to claim 1 wherein the aromatic carboxylic acid is salicylic acid.
 4. A process according to claim 1 wherein the aromatic carboxylic acid is o-phthalic acid. 